By shining a light on atmospheric turbulence, the Air Force's STARFIRE OPTICAL RANGE has taken the twinkle out of stars--and dramatically improved our vision of all that is above us

HERE ON PLANET EARTH, the obfuscation is relentless. We squint by day as the firmament pours down on us in blinding waves, veiling the mysteries of space. By night the stars twinkle, twinkle, hiding in plain sight behind that pulsing mirage. We see through a glass darkly--somewhat like trying to spy on beauty through textured-glass shower doors. The earth's atmosphere is the culprit, of course, scattering blue light all day and making the stars flicker at night, to the profound frustration of astronomers. Galileo, with his hand-ground lenses, experienced the blurring effects of atmospheric turbulence--chaotic pockets of hot and cold air present even on the clearest nights--and every stargazer since has settled for the same lousy reception. But at the Starfire Optical Range on Kirtland Air Force Base in Albuquerque, a team of military and civilian scientists did something about it: They looked up at the stars and took the twinkle out.

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It began with the simple if audacious idea of a smart mirror, one that could match the distortions of atmospherically whacked light waves with equal but opposite bends in its surface. As Robert Fugate, Starfire's chief scientist for atmospheric compensation from 1979 till his retirement this year, explains, "Horace Babcock at the Palomar Observatory suggested the flexible mirror fifty years ago; it took the last thirty years to work out the details."

For Rick Cleis, a computer wizard and one of the first to join the Starfire team in 1984 as a young second lieutenant, wrestling with those "details" was a MacGyver's dream of improvisational tinkering. "We didn't even have a telescope, just a tiny laser and a flat mirror on a gimbal pointed at Polaris," says Cleis, now chief scientist at Starfire. "We just started making our measurements. Nobody knew if it was possible."

As other labs tried their hands and failed, Starfire inherited their stuff--lots of increasingly sophisticated stuff. In its simplest form, this approach, known as adaptive optics, required a sensor device to measure the complex atmospheric turbulence instant by instant, a computerized translation of the measurements into zaps of electricity, and a very thin deformable mirror that could keep pace, making myriad tiny corrections in shape before the whole picture changed once again. All in all, it's an elegant solution, a dance with light, the distorted light waves leading, the deformable mirror following, so that the telescope could suddenly see as well as if there had been no atmosphere at all, as if this were all happening in space--but without the travel expense.

The system worked great, so long as it was aimed at bright objects beaming down enough distorted light to measure, but for a space-surveillance system, or a versatile astronomical tool, that was a serious weakness--sort of like the joke about the drunk who looks for his keys under the streetlight. Where the light source was weak, too few incoming photons meant a poor measurement of turbulence. Enter the laser guidestar, an artificial star that was like a movable streetlight in the sky, available wherever needed. By bouncing a laser beam off air molecules and measuring the turbulence with the reflected light, Starfire's scopes could look anywhere. It was like laser surgery for the collective eyes of mankind.

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Starfire's pioneering success with adaptive optics revolutionized ground-based optical astronomy, making possible high-resolution imaging with huge-aperture telescopes. "With AO, astronomers can talk about size again," Fugate says. "Bigger is better. You can make a thirty-meter scope on the ground, but to put it into space would cost the entire budget of France."

Today, deformable mirrors and guidestars are standard on the world's largest telescopes, gleaning unprecedented views of the far reaches of our galaxy, its black hole, and, with the added resolution necessary to distinguish proximal bright objects from a single blur, lots of new binary stars. "Every time you turn on a big AO telescope, you discover a new binary," says Starfire research scientist Jack Drummond, an expert in astronomical-image processing. Indeed, so many binaries have recently been found with adaptive optics that astronomers now theorize that our solo sun may be an exception--one necessary for our kind of life--and that Jupiter was meant to be its twin but just missed the cutoff mass to start cooking itself, and us.

STARFIRE'S LATEST EYE-OPENER, from the laser team led by Craig Denman, is a new and improved guidestar generated by a yellow-photon laser that excites sodium atoms fifty-six miles high in the mesosphere. Fugate still whistles with amazement at Denman's subtle divination of the one-in-a-million combination of wavelengths that elicits the yellow light--a long-sought grail in the laser community. Because of the special quality of its light, the new guidestar can slash through nearly the entire atmosphere and reflect off a diffuse band of meteorite debris, and from that higher altitude return a better beam, at a truer angle, for even bigger telescopes. Denman's prototype is now mounted on Starfire's big 3.5-meter scope; its even more efficient progeny will make possible such planned gargantuan ground-based telescopes as the Giant Magellan and the European Extremely Large, visionary projects about a decade away that will bring us closer, in Fugate's words, "to seeing to the edge of the universe, to the end of time."

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Not a bad peace dividend from the Air Force's Directed Energy Directorate Optics Division, whose primary mission is, after all, military; specifically, in its words, to "get laser beams to their targets (for weapons, communications, sensing)." As Fugate steps down, amid a hail of honors--he has an asteroid named after him, as well as Mount Fugate, the scree-strewn desert hilltop from which the Starfire Optical Range aims its now considerable hardware at the heavens--he leaves behind an Optics Division that has grown exponentially, from a team of 3 to about 120. The beat old trailers where mice skittered across computer keyboards at night have been replaced by the fifty-two-thousand-square-foot Air Force research lab where scientists, computer-hardware and software experts, electrical engineers, and other technicians can conceive, try out, and build just about any innovation they can imagine. Rick Cleis's little mirror has morphed into Starfire's world-class 3.5-meter telescope, weighing 275,000 pounds, its two-ton primary mirror cast in a one-off spinning oven, its bundles of cables like a dragon's veins, in overall complexity approaching a living being. It's a one-of-a-kind instrument, a telescope built by optical physicists for the study of telescopes, an eye that looks at itself as much as it looks at space, that sees the problems of seeing.

It's an impressive sight, the big scope lit up by the yellow glow of its sodium laser in the desert night. Freed from the constraints of a conventional slow-rotating dome by its unique retractable roof and three-tiered collapsible enclosure--like a giant steel camp cup--the big scope can slew rapidly across the sky for space-surveillance purposes. A rapidly moving telescope tracking an object blistering across space encounters another seeing problem, one familiar to all photographers and target shooters: platform jitter. Not only are we immersed in the "muck" (as Starfire scientists call the atmosphere), the whole planet trembles like a nervous chihuahua. Everywhere, at all times, everything is moving, a little or a whole lot. But what can't be stilled by sheer bulk and sunken foundations can be finessed with specialized mirrors. The same electromechanical pistons that shape the adaptive-optics mirrors hold the whirling primary mirror's true shape (to a precision of twenty-one nanometers, three thousand times finer than a human hair) while small, fast-steering mirrors cancel out additional jitter. When adaptive optics makes the jump to aiming weapons-grade lasers, whether on the ground or in the air, jitter control will mean the difference between shooting a shotgun or a rifle.

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Meanwhile, clear-sighted and steady as she goes, Starfire has already proved adaptive optics' value as a diagnostic tool for troubleshooting in space. When the Japanese lost contact with a satellite, Fugate got a telephone call from Jet Propulsion Laboratory, which built a payload on the vessel, requesting a picture. The ailing craft was due to fly over Albuquerque at 10:30 P.M., about five hundred miles up and zipping along at twenty thousand miles per hour. Up on the range, they aimed the big scope and turned on its camera. Five hours later, Starfire had the answer: The satellite's solar panel had failed to deploy. There it was, still rolled up, plainly visible in a high-resolution, eyeballable image.

"Space situational awareness" is the Air Force's catchall phrase for things that go bump in the eternal night. "The question is: How do we as a nation understand what's in space?" says Lieutenant Colonel Dennis Montera, the Optics Division's chief of analysis. "And once you know where things are, the tens of thousands of objects, all the nuts and bolts, the next question is: What are they doing?" The answer to both questions now seems obvious. You just take a small group of brilliant individuals, let their minds run free, add a sprinkle of salt from the mesosphere, and then simply take a look.

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